Colored soda-lime glass

ABSTRACT

The invention concerns a colored soda-lime glass comprising an amount of MgO more than 2%, an amount of Fe 2 O 3  less than 1.1%, and amount of MnO 2  less than 1300 ppm, an amount of Co more that 55 ppm and it has a selectivity (SE4) higher than 1.2 and a dominant wavelength λ D  not exceeding 490 nm and excitation purity (P) more than 10%. Said glass is particularly suited for rear side windows, back windows and glass sun roofs for motor vehicle.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from PCT Application No. PCT/EPOO/09756filed 4 Oct. 2000, which is based upon and claims priority from PCTApplication No. PCT/EP99/07467 filed 6 Oct. 1999, both of which arehereby incorporated by reference.

BACKGROUND OF THE INVENTION

The present invention relates to a coloured soda-lime glass comprisingthe main glass-forming constituents and colouring agents.

The term “soda-lime glass” is used in the broad sense here and relatesto any glass containing the following constituents, the quantity ofwhich is expressed as a percentage relative to the total weight ofglass:

Na₂O 10 to 20% CaO  0 to 16% SiO₂ 60 to 75% K₂O  0 to 10% MgO  0 to 10%Al₂O₃ 0 to 5% BaO 0 to 2% BaO + CaO + MgO 10 to 20% K₂O + Na₂O  10 to20%.

This type of glass is very widely used, for example, in the glazing forthe building or automotive sector. It is currently manufactured inribbon form using the float process. Such a ribbon can be cut intosheets which can then be bended or subjected to a treatment to reinforcetheir mechanical properties, e.g. thermal toughening.

It is generally necessary to relate the optical properties of a glasssheet to a standard illuminant. In the present description 2 standardilluminants are used: illuminant C and illuminant A as defined by theCommission Internationale de I'Éclairage (CIE). Illuminant C representsthe average daylight having a colour temperature of 6700 K. Thisilluminant is especially suitable for evaluating the optical propertiesof glazing intended for building as well as the colour of glazing formotor vehicles. Illuminant A represents the radiation of a Planckradiator at a temperature of about 2856 K. This illuminant representsthe light emitted by vehicle headlights and is essentially intended forevaluation of the optical properties of glazing intended for motorvehicles. The Commission Internationale de I'Éclairage has alsopublished a document entitled “Colorimétrie, Recommandations Officiellesde la C.I.E.” [Colorimetry, Official Recommendations of the CIE], (May1970) which describes a theory according to which colorimetriccoordinates for the light of every wavelength of the visible spectrumare defined so that they can be represented on a diagram with orthogonalaxes x and y, referred to as the CIE 1931 trichromatic diagram. Thistrichromatic diagram shows the representative location of the light ofevery wavelength (expressed in nanometres) of the visible spectrum. Thislocation is referred to as the “spectrum locus” and the light withcoordinates located on this spectrum locus is said to have 100%excitation purity with the appropriate wavelength. The spectrum locus iscompleted by a light called the purple boundary which joins the ends ofthe spectrum locus with coordinates corresponding to wavelengths 380 nm(violet) and 780 nm (red). The area contained between the spectrum locusand the purple boundary is that available for the trichromaticcoordinates of all visible light. The coordinates of light emitted byilluminant C, for example, correspond to x=0.3101 and y=0.3162. Thispoint C is considered to represent white light and therefore has anexcitation purity equal to zero for any wavelength. Lines can be drawnfrom point C towards the spectrum locus and any required wavelength, andany point located on these lines can be defined not only by itscoordinates x and y, but also as a function of the wavelengthcorresponding to the line on which it is located and its distance frompoint C relative to the total length of the wavelength line.Consequently, the hue of the light transmitted by a coloured glass sheetcan be described by its dominant wavelength and its excitation purityexpressed as a percentage.

The CIE coordinates of light transmitted by a coloured glass sheet willdepend not only on the composition of the glass but also on itsthickness. In the present description as well as in the claims, all theexcitation purity P and dominant wavelength λ_(D) values of thetransmitted light are calculated on the basis of the specific internalspectral transmission factors (TSI_(λ)) of a 5 mm thick glass sheet withilluminant C at a solid angle of observation of 2°. The specificinternal spectral transmission factor of a glass sheet is ruled solelyby the absorption of the glass and can be expressed by Beer-Lambert'slaw:

TSI_(λ)=e^(EAλ) where A_(λ) is the absorption coefficient of the glass(in cm⁻¹) at the considered wavelength, and E the thickness of the glass(in cm). In a first approximation, TSI_(λ) can also be represented bythe formula(I ₃ +R ₂)/(I ₁ −R ₁)

-   -   where I₁, is the intensity of the incident visible light on a        first face of the glass sheet, R₁ is the intensity of the        visible light reflected by this face, I₃ is the intensity of the        visible light transmitted from the second face of the glass        sheet, and R₂ is the intensity of the visible light reflected        towards the interior of the sheet by this second face.

The colour rendition index (R), expressed by a number in the range ofbetween 1 and 100, denotes the difference between a colour and theperception that an observer has of it when he/she looks through acoloured transparent screen. The more significant this difference is,the lower the rendition index of the colour in question will become.With a constant wavelength λ_(D), when the purity of the colour of theglass increases, the colour rendition index perceived through this glassdecreases. The colour rendition index is calculated according to thestandard EN 410. We will refer below to the rendition index of thecolour yellow (R_(j)) of a glass which denotes the distortions of thiscolour in relation to the colour perceived by an observer lookingthrough this glass.

The following are also used in the following description as well as theclaims:

-   -   the total light transmission with illuminant A (TLA) measured        for a thickness of 4 mm (TLA4) at a solid angle of observation        of 2°. This total transmission is the result of integration        between the wavelengths of 380 and 780 nm of the term: Σ        T_(λ).E_(λ).S_(λ)/Σ E_(λ).S_(λ), in which T_(λ) is the        transmission at wavelength λ, E_(λ) is the spectral distribution        of illuminant A and S_(λ) is the sensitivity of the normal human        eye as a function of wavelength λ;    -   the total energy transmission (TE), measured with a thickness of        4 mm (TE4). This total transmission is the result of integration        between the wavelengths of 300 and 2500 nm of the term: Σ        T_(λ).E_(λ)/Σ E_(λ). The energy distribution E_(λ) is the        spectral energy distribution of the sun at 30° above the        horizon, with an air mass equal to 2 and an inclination of the        glazing relative to the horizontal of 60°. This distribution,        referred to as “Moon distribution”, is defined in the standard        ISO 9050.    -   selectivity (SE), measured by the ratio of total light        transmission for illuminant A to total energy transmission        (TLA/TE);    -   total ultraviolet transmission, measured for a thickness of 4 mm        (TUV4). This total transmission is the result of the integration        between 280 and 380 nm of the term Σ T_(λ).U_(λ)/Σ U_(λ), in        which U_(λ) is the spectral distribution of the ultraviolet        radiation which has crossed the atmosphere determined in the        standard DIN 67507;    -   the Fe²⁺/total Fe ratio, sometimes referred to as the redox        ratio, which represents the value of the ratio in atomic weight        of Fe²⁺ relative to the total weight of iron atoms present in        the glass, and which is obtained by the formula:        Fe ₂₊ /Fe _(total)=[24.4495×log (92/τ₁₀₅₀)]/t−_(Fe203)    -   where τ₁₀₅₀ represents the specific internal transmission factor        of the glass of 5 mm at the wavelength 1050 nm. t−_(Fe203)        represents the total content of iron expressed in the form of        oxide Fe₂O₃ and measured via X-ray fluorescence.

SUMMARY OF THE INVENTION

The present invention relates to blue glasses in particular. Theseglasses can be used in architectural applications and as glazing inrailway carriages and motor vehicles. In the architectural application,glass sheets 4 to 6 mm thick will generally be used while in theautomotive field thicknesses of 1 to 5 mm are currently applied, inparticular for the formation of glazing for side windows and openingroofs.

The invention relates to a coloured soda-lime glass comprising the mainglass-forming constituents and colouring agents, characterised in thatit comprises:

-   -   i) a quantity of MgO expressed relative to the total weight of        glass which is more than 2%,    -   ii) a quantity of MnO₂ expressed relative to the total weight of        glass which is less than 1300 parts per million,    -   iii) a quantity of Fe₂O₃ expressed relative to the total weight        of glass which is less than 1.1%, the total quantity of iron        being expressed in the form of Fe₂O₃,    -   iv) a quantity of Co expressed relative to the total weight of        glass which is more than 55 parts per million, and in that it        has    -   v) a selectivity (SE4) greater than 1.2,    -   vi) a dominant wavelength (λ_(D)) less than or equal to 490 mm,        and    -   vii) excitation purity greater than 10%.

This combination of compositions and properties is advantageous in thatit allows a particularly aesthetically pleasing colour to be providedwhile assuring an increased selectivity which enables the restriction ofinterior heating of the spaces defined by glazing units according to theinvention.

It is desirable that the main constituents for forming the glassaccording to the invention contain a concentration of MgO of more than2% by weight relative to the total weight of glass, since this compoundpromotes the fusion of its constituents during the glass melt.

The energy and optical properties of a glass containing severalcolouring agents result from a complex interaction between these agents.In fact, these colouring agents exhibit a behaviour which is heavilydependent on their oxidation state and therefore on other elementslikely to influence this state.

Iron is present in the majority of glasses available on the market,especially in coloured glasses. The presence of Fe³⁺ provides the glasswith a slight absorption of visible light at low wavelength (410 and 440nm) and a very strong absorption band in the ultraviolet range(absorption band centred at 380 nm), while the presence of Fe²⁺ causesstrong absorption in the infrared range (absorption band centred at 1050nm). The presence of Fe³⁺ provides the glass with a light yellowcoloration, generally regarded as not very pleasing, while ferrous ions,Fe²⁺, provide a pronounced blue-green coloration. A strong concentrationof Fe²⁺ in the glass therefore allows the energy transmission TE to bereduced and a pleasing coloration to be provided. However, the presenceof iron in the bath of molten glass causes an absorption of infraredradiation which can hinder the heat diffusion in the glass productionfurnace and therefore make this production more difficult. Moreover,when the concentration of iron increases, the light transmission of theglass decreases.

The glass according to the invention contains less than 1.1% of Fe₂O₃relative to the total weight of glass, and preferably less than 1.0%.This iron content allows the glass according to the invention to beproduced in a traditional large-capacity furnace.

Advantageously, the glass according to the invention contains ferrousiron in a quantity, expressed in the weight of atoms of Fe²⁺ relative tothe total weight of iron atoms present in the glass, which is greaterthan 28% (Fe²⁺/total Fe ratio), preferably greater that 32%, andpreferably greater than 35%. This ratio enables a glass with a low TEand high selectivity to be obtained.

The glass according to the invention contains less than 1300 parts permillion (ppm) of MnO₂ relative to the total weight of glass. Theoxidising character of MnO₂ may influence the redox state of the iron,reduce the selectivity of the glass and also result in a violet hue.

The glass according to the invention contains more than 55 parts permillion of Co relative to the total weight of glass, advantageously morethan 60 parts per million of Co, and preferably more than 70 parts permillion of Co. The higher the Co content, the more the blue colour ofthe glass is accentuated.

In preferred forms, the glass according to the invention has a renditionindex for the colour yellow (R_(j)) greater than 98.5−0.74×P, preferablygreater than 101−0.74×P, and preferably greater than 104−0.74×P. Theserelations result, with a given purity of the glass, in very lowdistortions of the colour yellow as perceived by an observer through aglass sheet according to the invention.

Since the human eye is particularly sensitive to the colour yellow, ahigh value of the rendition index for this colour denotes that anobserver has a particularly natural perception of his/her environment asseen through a glass sheet according to the invention.

Equally, the glass according to the invention preferably has a TUV4 ofless than 30%. Such a value allows significant discoloration of objectssituated in a space defined by a glazed surface composed of the glassaccording to the invention to be prevented. This property isparticularly advantageous in the automotive-sector. A low ultravioletradiation transmission factor in fact enables the ageing anddiscoloration of interior fittings of the vehicles which have beenexposed to the effects of the sun to be prevented.

It is desirable that the glass according to the invention has a TLA4 ofless than 70%, preferably less than 65%, and preferably less than 60%,this making it particularly suitable for applications such as theformation of rear windows, rear side windows and glazed roofs in motorvehicles.

It is preferred that the glass according to the invention contains morethan 0.5% by weight of Fe₂O₃ (total iron), preferably more than 0.6%,and preferably more than 0.7% by weight of Fe₂O₃. Such contents enable ahigh selectivity of the glass to be achieved.

Furthermore, in the forms preferred according to the invention, theglass has a selectivity higher than 1.3, preferably higher than 1.4, andpreferably higher than 1.5.

This is particularly advantageous in terms of reducing the heating inspaces defined by glazing units made with glass according to theinvention.

Preferably, the glass according to the invention has a dominantwavelength (λ_(D)) and excitation purity (P) which, in a CIE 1931trichromatic diagram, are located inside a triangle, wherein the anglesare the point representing illuminant C and the points, of which thecoordinates (λ_(D), P) are (490, 19) and (476, 49) respectively,preferably (490, 19) and (480, 38). This corresponds to colorationswhich are regarded as particularly aesthetically pleasing.

Advantageously, the glass according to the invention has a dominantwavelength (λ_(D)) and excitation purity (P) which, in a CIE 1931trichromatic diagram, are located inside a trapezium, wherein the anglesare the points, of which the coordinates (λ_(D), P) are (480, 10), (480,38), (490, 19) and (490, 10) respectively, preferably (480, 15), (480,38), (490, 19) and (490, 15).

The glass according to the invention preferably has a dominantwavelength of less than or equal to 489 nm.

The glass according to the invention can have an excitation puritygreater than 10%, preferably greater than 15%, and preferably greaterthan 20%, this corresponding to particularly appreciated hues.

A coloured glass according to the invention can contain the followingcolouring agents, the quantity thereof being expressed as a percentagerelative to the total weight of the glass and the total quantity of ironbeing expressed in the form of Fe₂:

-   -   Fe₂O₃ more than or equal to 0.6% and less than 1.1%    -   FeO from 0.15 to 0.35%    -   Co from 0.0055 to 0.0120%.

The coloured glass having this composition of colouring agents has thefollowing optical properties:

-   -   35%<TLA4<60%    -   15%<TE4<40%    -   TUV4<25%    -   481 nm<λ_(D)≦490 nm    -   10%<P<25%.

The range of light transmission thus defined makes the glass accordingto the invention particularly suitable for preventing dazzling by thelight of the vehicle headlights when it is used for rear side windows oras rear window in vehicles. The corresponding range of energytransmission gives the glass its high selectivity.

According to a preferred variant of the invention, the glass can containthe following colouring agents, the quantity thereof being expressed asa percentage relative to the total weight of the glass and the totalquantity of iron being expressed in the form of Fe₂O₃:

-   -   Fe₂O₃ more than or equal to 0.9% and less than 1.1%    -   FeO from 0.25 to 0.33%    -   Co from 0.0060 to 0.0100%.

According to another preferred variant of the invention, the glass cancontain the following colouring agents, the quantity thereof beingexpressed as a percentage relative to the total weight of the glass andthe total quantity of iron being expressed in the form of Fe₂O₃:

-   -   Fe₂O₃ from 0.6 to 0.9%    -   FeO from 0.18 to 0.35%    -   Co from 0.0080 to 0.0130%.

The coloured glass having these compositions of colouring agents has thefollowing optical properties:

-   -   35%<TLA4<55%    -   20%<TE4<42%    -   TUV4<30%    -   479 nm<λ_(D)<488 nm    -   15%<P<35%.

The glass according to the invention can be coated with a layer ofmetallic oxides, which reduce the amount to which it is heated by solarradiation and therefore reduces the heating in the passenger compartmentof a vehicle using such glass for glazing.

The glasses according to the present invention can be produced bytraditional processes. With respect to raw materials, it is possible touse natural materials, recycled glass, cullet or a combination of thesematerials. The colouring agents do not have to be added in the formindicated, but this manner of giving the added quantities of colouringagents complies with current practice. In practice, iron is added inRouge form and cobalt in the form of hydrated sulphate such asCoSO₄.7H₂O or CoSO₄.6H₂O.

Other elements are sometimes present as impurities in the raw materialsused to manufacture the glass according to the invention, as is the casewith natural materials, recycled glass and cullet, but where theseimpurities do not give the glass properties outside the limits definedabove, these glasses are considered to be in conformity with the presentinvention.

The glass according to the invention preferably contains less than 2%,and preferably less than 1%, of titanium expressed by weight of TiO₂relative to the total weight of glass, or even less than 0.1% of TiO₂. Atoo great quantity of TiO₂ poses the risk of providing the glass with ayellow coloration which is not desirable.

In contrast, the presence of TiO₂ has the advantage of enabling the TUVto be reduced.

DETAILED DESCRIPTION

The present invention is illustrated below on the basis of specificexamples.

EXAMPLES 1 TO 49

Table I indicates the basic composition of the glass for informationpurposes and in a non-restrictive manner. It specifies the opticalproperties and proportions by weight of colouring agents of a glassaccording to the invention relative to the weight of this glass forinformation purposes and in a non-restrictive manner. These proportionsare determined by X-ray fluorescence of the glass and are converted tothe indicated molecular proportions. The MnO₂ content of examples 23 to49 is comprised between 150 and 250 parts per million relative to thetotal weight of glass.

The vitrification mixture can contain, if necessary, a reducing agentsuch as coke, graphite or slag, or an oxidising agent such as nitrate.In this case, the proportions of the other materials are adapted so thatthe composition of the glass remains unchanged.

TABLE I BASE GLASS ANALYSIS SiO₂ 71.5–71.9% Al₂O₃ 0.8% CaO 8.8% MgO 4.2%Na₂O 14.1%  K₂O 0.1% SO₃ 0.05–0.45%

TABLE II Fe2O3 FeO Fe²⁺/Fe(Tot) Co MnO2 TLA4 TE4 TUV4 λ_(D) P Ex. N° (%)(%) (%) (ppm) (ppm) (%) (%) (%) SE4 (nm) (%) Rj 1 1.01 0.27 39 64 8049.6 32.1 12.3 1.55 486 17.6 93.7 2 1.00 0.29 32 64 100 48.2 30.3 12.01.59 486 18.6 93.3 3 1.04 0.33 35 62 90 46.9 28.2 12.6 1.66 486 20.092.8 4 1.03 0.39 42 65 80 44.7 25.7 14.2 1.74 485 23.2 91.9 5 0.99 0.4753 100 50 36.1 21.6 16.4 1.68 482 34.2 90.7 6 1.02 0.39 42 71 40 43.825.7 14.4 1.71 484 24.5 91.9 7 1.01 0.49 54 70 70 41.0 22.8 17.0 1.80484 29.1 90.4 8 1.02 0.36 39 109 60 38.1 24.7 13.1 1.55 482 29.7 92.3 91.02 0.46 50 69 110 44.7 26.1 12.9 1.71 485 22.5 91.1 10 0.90 0.22 27 5860 52.8 36.9 16.6 1.43 485 15.5 11 0.89 0.23 29 62 80 51.7 36.6 17.01.41 485 16.5 12 0.85 0.27 35 65 70 49.7 33.5 19.2 1.48 484 20.3 13 0.910.31 38 71 60 45.6 28.9 16.9 1.58 484 22.4 14 0.95 0.30 35 63 90 47.829.7 15.2 1.61 485 20.2 15 0.98 0.31 35 58 60 48.4 28.9 14.0 1.67 48619.3 16 0.61 0.23 42 60 50 54.3 37.9 26.6 1.43 483 20.2 17 0.65 0.25 4362 80 52.5 35.7 25.0 1.47 484 20.9 18 0.67 0.25 41 60 70 53.3 36.4 24.11.46 484 20.0 19 0.72 0.28 43 62 60 50.6 32.6 22.2 1.55 484 21.3 20 0.740.27 40.5 61 90 51.2 33.5 21.3 1.53 484 20.5 21 0.78 0.27 38 70 100 48.332.4 19.6 1.49 484 21.9 22 0.81 0.35 48 65 80 45.8 25.6 18.9 1.79 48423.6 23 0.78 0.31 44 115 41.9 28.3 22.1 1.48 480.6 31.0 24 0.8 0.29 40100 45.1 30.9 20.9 1.46 481.5 26.8 25 0.825 0.26 35 80 49.4 34.2 19.31.45 483.1 21.4 26 0.85 0.23 30 75 51.2 36.5 17.8 1.40 483.8 18.7 270.875 0.24 30 65 52.4 36.4 17.0 1.44 485.0 16.9 28 0.85 0.27 35 130 40.530.3 19.2 1.34 480.2 30.6 29 0.825 0.33 45 90 45.0 28.1 20.8 1.60 482.226.7 30 0.79 0.32 45 130 38.9 26.6 22.2 1.46 480.1 34.2 31 0.83 0.34 4687 45.1 27.6 20.7 1.63 482.5 26.5 32 0.71 0.22 35 80 51.7 37.4 22.4 1.38482.5 21.5 33 0.69 0.28 45 130 40.8 29.4 24.9 1.39 479.5 34.3 34 0.750.27 40 100 46.1 32.3 22.2 1.43 481.2 26.9 35 0.65 0.23 39 89 50.2 36.424.7 1.38 481.1 24.6 36 0.61 0.21 38 82 52.4 38.5 25.5 1.36 481.3 23.037 0.75 0.29 43 98 45.5 30.7 22.5 1.48 481.3 27.6 38 0.73 0.26 39 12642.4 31.8 22.9 1.33 479.7 31.4 39 0.76 0.29 42 114 43.0 30.1 22.4 1.43480.5 30.2 40 0.64 0.22 39 86 50.9 36.9 24.9 1.38 481.2 24.1 41 0.630.20 35 80 53.2 39.7 24.5 1.34 481.5 21.6 42 0.65 0.18 31 85 53.1 41.023.5 1.30 481.4 21.1 43 0.69 0.21 34 90 50.6 37.9 22.9 1.34 481.3 23.044 0.73 0.23 35 92 49.2 36.1 22.0 1.36 481.5 23.7 45 0.76 0.225 33 9448.9 36.2 20.9 1.35 481.6 23.3 46 0.79 0.27 38 92 47.2 32.8 20.8 1.44481.9 24.7 47 0.83 0.26 35 90 47.6 33.4 19.3 1.43 482.4 23.2 48 0.860.27 35 83 48.2 33.0 18.4 1.46 483.1 21.9 49 0.88 0.28 35 90 46.7 32.017.9 1.46 482.7 23.2

1. Colored soda-lime glass comprising the main glass-formingconstituents and coloring agents, characterised in that it comprises: i)a quantity of MgO expressed relative to the total weight of glass whichis more than 2%, ii) a quantity of MnO₂ expressed relative to the totalweight of glass which is from 40 to 250 parts per million, iii) aquantity of Fe₂O₃ expressed relative to the total weight of glass whichis less than 1.1%, the total quantity of iron being expressed in theform of Fe₂O₃, iv) a quantity of Co expressed relative to the totalweight of glass which is more than 55 parts per million, and in that ithas v) a selectivity (SE4) greater than 1.2, vi) a dominant wavelength(λ_(D)) less than or equal to 490 nm, and vii) excitation purity (P)greater than 10%.
 2. Colored glass according to claim 1, characterisedin that it includes at least one of the following features (A) through(M): (A) it has a rendition index for the colour yellow (Rj)of >98.5−0.74×P; (B) it contains ferrous iron in a quantity, expressedin the weight of atoms of Fe²⁺ relative to the total weight of ironatoms present in the glass, which is greater than 28% (Fe²⁺/total Feratio); (C) it has a dominant wavelength (λ_(D)) of less than 489 nm;(D) it has an excitation purity higher than 15%; (E) it has aselectivity (SE4) greater than 1.4; (F) it comprises a quantity of Coexpressed relative to the total weight of glass which is more than 60parts per million; (G) it has a TUV4 of less than 30%; (H) it has a TLA4of less than 70%; (I) it comprises a quantity of Fe₂O₃ expressedrelative to the total weight of glass which is more than 0.5%; (J) ithas a dominant wavelength (λ_(D)) and excitation purity (P) which, in a1931 CIE trichromatic diagram, are located inside a triangle, whereinthe angles are the point representing illuminant C and the points, ofwhich the coordinates (λ_(D), P) are (490, 19) and (476, 49)respectively; (K) it comprises the following colouring agents, thequantity thereof being expressed as a percentage relative to the totalweight of the glass and the total quantity of iron being expressed inthe form of Fe₂O₃: Fe₂O₃ more than or equal to 0.6% and less than 1.1%FeO from 0.15 to 0.35% Co from 0.0055 to 0.0120%; (L) it has thefollowing optical properties: 35%<TLA4<60% 15%<TE4<40% TUV4<25% 481nm<λ_(D)<490 nm 10%<P<25%; (M) it comprises a quantity of TiO₂ expressedrelative to the total weight of glass, which is less than 2%.
 3. Coloredglass according to claim 2, characterised in that it includes at leasttwo of the aforementioned features (A) through (M).
 4. Colored glassaccording to claim 2, characterised in that it includes at least threeof the aforementioned features (A) through (M).
 5. Colored glassaccording to claim 2, characterised in that it includes at least four ofthe aforementioned features (A) through (M).
 6. Colored glass accordingto claim 2, characterised in that it includes at least five of theaforementioned features (A) through (M).
 7. Colored glass according toclaim 2, characterised in that it includes all of the aforementionedfeatures (A) through (M).
 8. Colored glass according to claim 2, furthercharacterised in that when feature (B) is selected, the amount offerrous iron is greater than 32%.
 9. Colored glass according to claim 2,further characterised in that when feature (E) is selected, SE4 isgreater than 1.5.
 10. Colored glass according to claim 2, furthercharacterised in that when feature (H) is selected, TLA4 is less than65%.
 11. Colored glass according to claim 2, further characterised inthat when feature (H) is selected, TLA4 is less than 60%.
 12. Coloredglass according to claim 2, further characterised in that when feature(I) is selected, the quantity of Fe₂O₃ is more than 0.6%.
 13. Coloredglass according to claim 2, further characterised in that when feature(I) is selected, the quantity of Fe₂O₃ is more than 0.7%.
 14. Coloredglass according to claim 2, further characterised in that when feature(J) is selected, it has a dominant wavelength (λ_(D)) and excitationpurity (P) which, in a CIE 1931 trichromatic diagram, are located insidea triangle, wherein the angles are the point representing illuminant Cand the points, of which the coordinates (λ_(D), P) are (490, 19) and(480, 38) respectively.
 15. Colored glass according to claim 2, furthercharacterised in that when feature (K) is selected, the quantity ofcolouring agents being expressed as a percentage relative to the totalweight of the glass and the total quantity of iron being expressed inthe form of Fe₂O₃ are: Fe₂O₃ more than or equal to 0.9% and less than1.1% FeO from 0.25 to 0.33% Co from 0.0060 to 0.0100%.
 16. Colored glassaccording to claim 15, characterised in that it has the followingoptical properties: 35%<TLA4<55% 20%<TE4<42% TUV4<30% 479 nm<λ_(D)<488nm 15%<P<35%.
 17. Colored glass according to claim 2, furthercharacterised in that when feature (I) is selected, the quantity ofcolouring agents being expressed as a percentage relative to the totalweight of the glass and the total quantity of iron being expressed inthe form of Fe₂O₃ are: Fe₂O₃ from 0.6% to 0.9%; FeO from 0.18 to 0.35%Co from 0.0080 to 0.0130%.
 18. Colored glass according to claim 17,characterised in that it has the following optical properties:35%<TLA4<55% 20%<TE4<42% TUV4<30% 479 nm<λ_(D)<488 nm 15%<P<35%. 19.Colored glass according to claim 2, further characterised in that whenfeature (M) is selected, the quantity of TiO₂ expressed relative to thetotal weight of glass, is less than 1%.
 20. Colored glass according toclaim 2, further characterised in that when feature (M) is selected, thequantity of TiO₂ expressed relative to the total weight of glass, isless than 0.1%.
 21. Colored glass according to claim 1, characterised inthat it forms part of the composition of glazing for vehicles.